1. Field of the Invention (Technical Field):
The present invention relates to methods and apparatuses for joining sections of a missile.
2. Description of Related Art:
Current missile assembly practices 10 typically use screws 12 and nut-plates 14 to join the two mating halves of missile sections together, as shown in FIGS. 1 and 2. The installation time and machining time required for this can be long. Each section must have the correct number of precision holes drilled and countersunk to accept the screw, and the mating section must have 3 holes per fastener drilled, one for the body of the fastener and two for the attachment of the nut plate. Installation of the nut plate rivets requires the mixing of a corrosion protection barrier, typically polysulfide.
The present invention employs a Nitinol ring clamp, which simply requires that both mating pieces have the same approximate groove feature machined into the end where the clamp will rest. The clamp sections and the Nitinol rings are positioned, and then, through the use of direct resistance heating for a maximum of about 10 seconds to fully seat the rings. The two sections are now joined via a Marmon clamp being retained by a Nitinol ring. Assembling the sections together provides a strong joint by nature of the Marmon clamp and it also reduces the assembly time process.